Window frame assembly



FIG. 1 is a perspective view of my new window frame assembly;

FIG. 2 is a front elevational view thereof; and,

FIG. 3 is a right side elevational view thereof; with the left side elevational view being a mirror image thereof.

The broken lines are for illustrative purposes only and form no part of the claimed design. 

The ornamental design for a window frame assembly, as shown and described. 